Containers

ABSTRACT

A compartmented container, such as an aerosol container, has a plastics pouch ( 12 ) attached to a top component such as an aerosol cone ( 1 ). The cone is typically formed of steel laminated with polypropylene, and the pouch is attached to the cone by means of a platics/plastics heat-sealed bond using the polypropylene surface layer of the cone. The pouch is attached to the cone ( 1 ) at an area away from that used to attach the cone to an aerosol container with a double seam. The cone typically has an annular countersink ( 4 ) and the pouch is attached either to the outer countersink wall ( 5 ) or the inner countersink wall ( 6 ).

BACKGROUND OF THE INVENTION

The present invention relates to compartmented containers i.e.containers having a bag or diaphragm to separate the interior of thecontainer into at least two sections. Such compartmented containers havefound widespread use in aerosols where it is desirable to separate thepropellant gases from the contents to be dispensed from the container.

UK patent application No. 2024334A is an example of such a compartmentedaerosol container, which uses an adhesive to secure a plastics pouch tothe sidewall of the aerosol can. An alternative type of compartmentedaerosol container is shown in EP0354137A, in which an injection mouldedshoulder is glued to an aerosol can body, a pouch being bonded to aportion of the shoulder insert. More commonly, a metallic top componentis provided, and the pouch or bag is secured by crimping the top of thebag into the double seamed joint between the can body and the topcomponent. An example of this type of container is GB2027130A Enrichcrimps a pouch by means of the double seam, but is also subjected to aheat treatment to bond the pouch and repair any tears in the pouchcaused by the double seaming. The present invention attempts to avoidthe use of adhesives, and the problems of tearing the bag when it issecured by means of the double seam.

SUMMARY OF THE INVENTION

Accordingly there is provided a method of manufacturing a compartmentedcontainer characterised by the steps of:

i. forming a plastics pouch being open at at least one of its ends;

ii. forming a metallic top component having at least one surface thereofcoated with a polymeric layer;

iii. heat-sealing the often end of the pouch and the top component oneto the other by means of a plastics/plastics bond between the pouch andthe polymeric layer of the top component;

iv. inserting the pouch into a tubular container body such that the topcomponent is adjacent one open end of the container body; and

v. securing the top component onto the container body by means of aseaming operation.

The top component preferably includes an annular countersink, and theopen end of the pouch is heat-sealed to a wall of the annularcountersink. Preferably the pouch is heat-sealed to the top component bymeans of an induction heater. Alternatively, the pouch may beheat-sealed to the top component by means of the injection of a line ofmolten polymer material in order to bond the panel to the top componentone to the other. In this instance the molten polymer material ispreferably polypropylene.

The plastics pouch is conveniently formed as a continuous tube andsubsequently cut to length. One end of the pouch may be closed andsealed prior to heat-sealing the opposite end to the top component, butmore preferably one end is heat-sealed to the top component, and theopposite end is closed and sealed prior to insertion of the pouch in thetubular container.

According to a further aspect of the invention there is provided acompartmented container comprising a tubular container body having anopen upper end, a plastics pouch having a closed lower end and an openupper end, and a top component connected to and closing the containerbody by means of a double seam, the top component being formed of metaland having at least its inner surface coated with a polymeric layercharacterised in that the open upper end of the plastics pouch isheat-sealed to the top component at an area away from that of the doubleseam by means of a plastics/plastics bond between the pouch and thepolymeric layer on the top component.

The term “coated” is herein meant to include metal/polymer laminatessuch as those of our European patent No. EP 0312302B, as well as othercoated techniques for producing metal coils coated with plasticsmaterial as will be known by those skilled in the art. Preferably one orboth of the tubular container body and the top component are formed ofsteel coated with a polymeric layer. Conveniently one or both of thetubular container body and the top component have at least their innersurface coated with a layer of polypropylene. Preferably thecompartmented container is an aerosol container, and the top componentis conveniently an aerosol cone.

According to a further aspect of the invention there is provided, incombination, a top component for an container and a plastics pouch, thetop component being formed of metal and having at least one surfacethereof coated with a polymeric layer, the top component having aseaming flange portion adapted to be used to attach the top component toa container body by means of a double seam, the plastics pouch beingopen at at least one of its ends, characterised in that the open end ofthe pouch is heat-sealed to the top component at an area away from theseaming flange portion by means of a plastics/plastics bond between thepouch and the polymeric layer of the top component. Preferably theplastics pouch is open at one end and closed at the other end, ready forreceiving the conents to be dispensed from the container.

The invention will now be further described, by way of example only,with reference to the accompanying drawings, in which;

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1a to 1 c are schematic views of a combination of aerosol topcomponent and plastics pouch in accordance with the present invention;

FIG. 2 is a schematic view of an alternative embodiment of combinationin accordance with the present invention;

FIG. 2(a) is a schematic view illustrating the combination of a cone andbag inserted into an aerosol container.

FIG. 2(b) is a schematic view of the combination of FIG. 2(a), andillustrates the cone double seamed to the body of the aerosol container.

FIG. 3 is a flow diagram showing the manufacture and assembly of aerosolcontainers in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1a, an aerosol top component known as a cone is showngenerally at 1 and comprises an external flange 2, an internal valve cuporifice 3, and between the two a downwardly depending countersink 4. Anouter countersink wall 5 connects the flange 2 to the countersink 4,whilst an inner countersink wall 6 connects the countersink 4 to thevalve cup orifice 3, terminating in a curl 7. The cone 1 is formed ofsteel laminated with polypropylene/polymeric layer (PL).

A plastics tube is shown at 8, also formed of polypropylene, and havingopen ends 9 and 10 as shown in FIG. 1a. FIG. 1b shows the tube 8 beingapplied to the cone 1, with an opening 0 at the open end 9 being fittedover the countersink 4 to form an intimate contact with the outercountersink wall 5. Heat is then locally applied, by means of aninduction heater (not shown) in order to form a plastics/plasticsheat-sealed bond B between the polypropylene of the tube 8 and that ofthe polypropylene surface layer PL of the aerosol cone 1. Once the tube8 and cone 1 have been secured one to the other, the opposite end 10 ofthe tube is formed into a gusset 11 and sealed. The tube 8 is now formedinto a bag 12 attached to the aerosol cone 1, and the combination ofcone and bag can then be inserted into an aerosol container, such as theaerosol container AC of FIG. 2(a).

The alternative version of FIG. 2 is similar to that of FIGS. 1a to 1 cand like parts are indicated by means of like reference numerals. Theconstruction of FIG. 2 differs from FIGS. 1a to 1 c in that the tube 8is attached to the inner countersink wall 6 radially inboard of aterminal perpheral edge PE of the external flange 2 of the aerosolcontainer AC. As before, a heat-sealed bond B is formed between thepolypropylene of the tube 8 and the polymeric layer PL on the surface ofthe cone.

FIG. 3 indicates the manufacuring process associated with one embodimentof the invention. Polypropylene film of thickness 100μ is fed from reelstock 12 and folded into a tube at a folding station 13. The overlappingside seam is welded at 14 and the resulting tube is cut to length atcutting station 15. An accumulator 16 stores the tubes and feeds them toa turret header 17 via a feeder 18.

At the first station of the header aerosol cans are loaded intoposition. At the second station the tubes are loaded onto mandrels, andthe tubes and cones are brought together at the third station. Aninduction heater applies heat to seal the tubes and the cones one to theother at the fourth and fifth stations, and the resulting combination isallowed to cool through the sixth to eighth stations. At the ninthstation the mandrel is withdrawn, and the combination is ejected at thetenth station. The open end of the tube is next formed into a gusset ata base forming station 19, and sealed in place at the sealing station20. The resulting combination, as shown in FIG. 1c or 2 depending on theembodiment, is then inserted into an aerosol can body at insertionstation 21. The cone is then double seamed (DS of FIG. 2(b)) onto thecan body at a seamer 22, and then the double seamed cone and can bodyFIG. 2(b) is passed to a bung insertion station 23, where a rubber bungis. inserted into a small aperture at the base of the aerosol can body.The container is then tested before leaving to be filled with product,after which a valve cup is applied to close the valve cup orifice, and apropellant is introduced through the base of the can via the rubberbung.

As can be seen from the above description, the heat-sealing of the bagallows a number of different options for the provision of the bag withinthe aerosol container. Although the use of a monolayer polypropylene baghas been described, alternative materials may be employed, includingmultilayer arrangements with barrier materials such as EVOH, PVdC,Polyamides or Polyesters, or even non-polymeric barrier materials suchas metal foils or ceramic materials.

Although a preferred embodiment of the invention has been specificallyillustrated and described herein, it is to be understood that minorvariations may be made in the apparatus without departing from thespirit and scope of the invention, as defined the appended claims.

What is claimed is:
 1. A method of manufacturing a compartmentedcontainer (AC) comprising the steps of: i. forming a plastic pouch (12)open at least at one of its ends (9); ii. forming a metallic aerosoldome top component (1) having an outer depending wall (5) and a domeshaped inner wall (6) ascending to an opening, said dome shaped innerwall (6) including an inner surface thereof coated with a polymericlayer (PL); iii. heat-sealing the at least one open end (9) of the pouch(12) and the aerosol dome top component (1) to each other by means of aplastic-to-plastic bond (B) between the pouch (12) and the polymericlayer (PL) upon the dome shaped inner wall inner surface of the aerosoldome top component (1); iv. inserting the pouch (12) into a tubularcontainer body (AC) such that the aerosol dome top component (1) isadjacent one open end of the container body (AC); and v. securing theaerosol dome top component (1) onto the container body (AC) by means ofa seaming operation (DS) between the container body one open end and aterminal peripheral portion (PE) of the aerosol dome top component (1)radially outboard of the plastic-to-plastic bond (B) whereby the latteris not adversely affected during the seaming operation.
 2. The methodaccording to claim 1 wherein the pouch is heat-sealed to the aerosoldome top component dome shaped inner wall inner surface by means of aninduction heater.
 3. The method according to claim 1 wherein the pouchis heat-sealed to the aerosol dome top component dome shaped inner wallinner surface by means of the injection of a line of molten polymermaterial in order to bond the pouch and the aerosol dome top componentone to the other.
 4. The method according to claim 3 wherein the moltenpolymer material is polypropylene.
 5. The method according to claim 1wherein the plastic pouch (12) is formed as a continuous tube and issubsequently cut to length.
 6. The method according to claim 1 includingthe step of closing and sealing another end of the pouch opposite the atleast one end heat-sealed to the aerosol dome top component prior to theinsertion of the pouch (12) into the tubular container.
 7. Acompartmented container comprising a tubular container body (AC) havingan open upper end, a plastic pouch (12) having a closed lower end (10)and an open upper end (9), a metallic aerosol dome top component (1)connected to and closing the container body (AC) by means of a doubleseam (DS), the aerosol dome top component (1) having an outer dependingwall (5) and a dome shaped inner wall (6) ascending to an opening, saiddome shaped inner wall (6) including an inner surface coated with apolymeric layer (PL), and the open upper end (9) of the plastic pouch(12) being heat-sealed to the aerosol dome top component (1) at aperipheral surface radially inboard of the double seam (DS) by means ofa plastic-to-plastic bond (B) between the pouch (12) and the polymericlayer (PL) on the aerosol dome top component dome shaped inner wallinner surface whereby the plastic-to-plastic bond (B) is not adverselyaffected during the forming of the double seam (DS).
 8. The containeraccording to claim 7 wherein at least one of the tubular container bodyand the aerosol dome top component are formed of steel coated with apolymeric layer.
 9. The container according to claim 7 wherein at leastone of the tubular container body and the aerosol dome top componenthave at least their inner surface coated with a layer of polypropylene.10. The container according to claim 11 wherein the top component (1) isan aerosol cone.
 11. A combination comprising an aerosol dome topcomponent (1), a container (AC) and a plastic pouch (12); the aerosoldome top component (1) being formed of metal and having an outerdepending wall (5) and a dome shaped inner wall (6) ascending to anopening, said dome shaped inner wall (6) including an inner surfacecoated with a polymeric layer (PL), the aerosol dome top component (1)having a seaming flange portion (2) adapted to be used to attach theaerosol dome top component (1) to the container body (AC) by means of adouble seam (DS), the plastic pouch (12) being open at least at one ofits ends (9), and the open end (9) of the plastic pouch (12) beingheat-sealed to the aerosol dome top component dome shaped inner wallinner surface radially inboard of the seaming flange portion (2) bymeans of a plastic-to-plastic bond (B) between the pouch (12) and thepolymeric layer (PL) of the aerosol dome top component (1) whereby theplastic-to-plastic bond (B) is not adversely affected during the formingof the double seam.
 12. The combination according to claim 11 whereinthe plastic pouch (12) is open at one end and closed at the other end.13. The container according to claim 9 wherein at least one of thetubular container body and the aerosol dome top component have at leasttheir inner surface coated with a layer of polypropylene.
 14. A methodof manufacturing a compartmented container comprising the steps of: i.forming a plastic pouch (12) having an opening (0) at least at one ofits ends (9); ii. forming a metallic aerosol dome top component (1)including an external flange (2) terminating at a peripheral edge (PE)and including an outer depending wall (5) and a dome shaped inner wall(6) ascending to an opening, said dome shaped inner wall (6) includingan inner surface coated with a polymeric layer (PL); iii. heat-sealingthe at least one open end (9) of the pouch (12) and the dome shapedinner wall (6) of the aerosol dome top component (1) to each other bymeans of a plastic-to-plastic bond (B) between the plastic pouch (12)and the polymeric layer (PL) of the aerosol dome top component domeshaped inner wall inner surface; iv. inserting the pouch (12) into atubular container body (AC) such that the aerosol dome top component (1)is adjacent one open end of the container body (AC); and v. securing theaerosol dome top component (1) to the container body (AC) by means of aseaming operation (DS) between the container body one open end and theexternal flange (2) of the aerosol dome top component (1) radiallyoutboard of the plastic-to-plastic bond (B) whereby theplastic-to-plastic bond (B) is not adversely affected during the seamingoperation.
 15. The method as defined in claim 22 wherein theheat-sealing is performed by induction heating.
 16. The method asdefined in claim 22 wherein the pouch is heat-sealed to the innersurface of the aerosol dome top component dome shaped inner wall innersurface by means of injection of a line of molten polymer material inorder to bond the pouch and the aerosol dome top component one to theother.
 17. A compartmented container comprising a tubular body (AC)having an open upper end, a plastic pouch (12) having a closed lower end(10) and an open upper end (9); a metallic aerosol dome top component(1) having an external flange (2) terminating at a peripheral edge (PE),an outer depending wall (5) and a dome shaped inner wall (6) ascendingto an opening with an inner surface of said dome shaped inner wall (6)being coated with a polymeric layer (PL); the open upper end (9) of theplastic pouch (12) being heat-sealed to the inner surface of the innerdome shaped wall (6) of the aerosol dome top component (1) radiallyinboard of a double seam (DS) securing the container body (AC) to theaerosol dome top component (1) whereby the plastic-to-plastic bond (B)is not adversely affected during the forming of the double seam (DS).